test:Another bug.

Author: antononcube

xt/30-bugs.rakutest

@@ -11,4 +11,9 @@ subtest {
     is Graph.new(vertexes => ["1", "2"], edges => []).vertex-list, <1 2>;
 }, "has vertexes and no edges graph";
 
+subtest {
+    is-deeply Graph.new(^5, []).adjacency-list, {0 => {}, 1 => {}, 2 => {}, 3 => {}, 4 => {}};
+    is-deeply Graph.new((^5), []).index-graph(10).vertex-list, <10 11 12 13 14>;
+}, "indexed graph over no edges";
+
 done-testing;